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Finite Element Analysis of 3-D Electromagnetic Field in Bloom Continuous Casting Mold

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Journal of Iron and Steel Research International 2007年第3期14卷 6-12页

作者： LIU Xu-dong yang xiao-dong ZHU Miao-yong CHEN Yong yang Su-bo School of Materials and Metallurgy Northeastern University Shenyang 110004 Liaoning China Iron and Steel Research Institute Panzhihua Iron and Steel Group Co Panzhihua 617062 Sichuan China

Three-dimensional finite element model of electromagnetic stirrer was built to predict magnetic field in a bloom continuous casting mold for steel during operation. The effects of current intensity, current frequency, and mold copper plate thickness on the magnetic field distribution in the mold were investigated. The results show that the magnetic induction intensity increases linearly with the increase in current intensity and decreases with the increase in current frequency. Increasing current intensity and frequency is available in increasing the electromagnetic force. The Joule heat decreases gradually from surface to center of bloom, and a maximum Joule heat can be found on corner of bloom. The prediction of magnetic induction intensity is in good agreement with the measured values.

关键词： mold electromagnetic stirring finite element analysis numerical simulation

Entanglement Evolution of a 2-Qutrit System Interacting with a Fermionic Bath

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Communications in Theoretical Physics 2005年第2X期44卷 274-278页

作者： MA xiao-San WANG An-Min yang xiao-dong XU Feng Department of Modern Physics University of Science and Technology of China Hefei 230026 China

Based on the algebraic entanglement measure proposed [G. Vidal et al., Phys. Rev. A 65 (2002) 032314],we study the entanglement evolution of both pure quantum states and mixed ones of 2-qutrit system in a symmetrybroken environment consisting of a fermionic bath. Entanglement of states will decrease or remain constant under the influence of environment, and the class of states which remain unchanged has been found out.

关键词： entanglement evolution 2-qutrit state fermionic bath

DYNAMIC STABILITY OF AXIALLY MOVING VISCOELASTIC BEAMS WITH PULSATING SPEED

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Applied Mathematics and Mechanics(English Edition) 2005年第8期26卷 989-995页

作者： yang xiao-dong（杨晓东） CHEN Li-qun（陈立群） Department of Engineering Mechanics Shenyang Institute of Aeronautical Engineering Shenyang 110034 P. R. China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 P. R. China Department of Mechanics Shanghai University Shanghai 200A.A.A. P. R. China

Parametric vibration of an axially moving, elastic, tensioned beam with pulsating speed was investigated in the vicinity of subharmonic and combination resonance. The method of averaging was used to yield a set of autonomous equations when the parametric excitation frequency is twice or the combination of the natural frequencies. Instability boundaries were presented in the plane of parametric frequency and amplitude. The analytical results were numerically verified. The effects of the viscoelastic damping, steady speed and tension on the instability boundaries were numerically demonsWated. It is found that the viscoelastic damping decreases the instability regions and the steady speed and the tension make the instability region drift along the frequency axis.

关键词： subharmonic resonance averaging method stability of vibration axially moving beam

Assimilation of Remote Sensing and Crop Model for LAI Estimation Based on Ensemble Kalman Filter

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Agricultural Sciences in China 2011年第10期10卷 1595-1602页

作者： LI Rui LI Cun-jun dong Ying-ying LIU Feng WANG Ji-hua yang xiao-dong PAN Yu-chun Beijing Research Center for Information Technology in Agriculture Beijing 100097 P.R.China Information Engineering Institute Capital Normal University Beijing 100048 P.R. China Chengdu Dawan High School Chengdu 610300 P.R.China

Data assimilation in agricultural remote sensing research is of great significance to integrate with remote sensing observations and model simulations for parameters estimation. The present investigation not only designed and realized the Ensemble Kalman Filtering algorithm （EnKF） assimilation by combing the crop growth model （CERES-Wheat） with remote sensing data, but also optimized and updated the key parameters （LAI） of winter wheat by using remote sensing data. Results showed that the assimilation LAI and the observation ones agreed with each other, and the R2 reached 0.8315. So assimilation remote sensing and crop model could provide reference data for the agricultural production.

关键词： crop model assimilation Ensemble Kalman Filter algorithm leaf area index

Assessment of Land Suitability Potentials for Selecting Winter Wheat Cultivation Areas in Beijing,China,Using RS and GIS

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Agricultural Sciences in China 2011年第9期10卷 1419-1430页

作者： WANG Da-cheng LI Cun-jun SONG xiao-yu WANG Ji-hua yang xiao-dong HUANG Wen-jiang WANG Jun-ying ZHOU Ji-hong Institute of Agricultural Remote Sensing and Information Technology Zhejiang University Hangzhou 310029 P.R. China Beijing Research Center for Information Technology in Agriculture Beijing 100097 P.R.China Agricultural Technology Extension Station in Beijing Beijing 100029 P.R.China

It is very important to provide reference basis for winter wheat quality regionalization of cultivation area. The aim of this article was based on factors affecting wheat quality and setting realistic spatial models in each part of the land for assessment of land suitability potentials in Beijing, China. The study employed artificial neural network （ANN） analysis to select factors and evaluate the relative importance of selected environment factors on wheat grain quality. The spatial models were developed and demonstrated their use in selecting the most suitable areas for the winter wheat cultivation. The strategy overcomes the non-accurate traditional statistical methods. Satellite images, toposheet, and ancillary data of the study area were used to find tillable land. These categories were formed by integrating the various layers with corresponding weights in geographical information system （GIS）. An integrated land suitability potential （LSP） index was computed considering the contribution of various parameters of land suitability. The study demonstrated that the tillable land could be categorized into spatially distributed agriculture potential zones based on soil nutrient and assembled weather factors using RS and GIS as not suitable, marginally suitable, moderately suitable, suitable, and highly suitable by adopting the logical criteria. The sort of land distribution map made by the factors with their weights showed more truthfulness.

关键词： LSP ANN suitable areas wheat RS and GIS

Effects of Lodging at Different Filling Stages on Rice Yield and Grain Quality

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Rice science 2012年第4期19卷 315-319页

作者： LANG You-zhong yang xiao-dong WANG Mei-e ZHU Qing-sen Key Laboratory of Crop Genetics and Physiology of Jiangsu Province Yangzhou University

The effects of lodging of rice plants from 20 d after full heading to maturity on yield and grain quality were investigated with a hybrid rice combination Liangyoupeijiu and a japonica rice cultivar CY-6. The results showed that, except for brown rice rate, almost all parameters for yield and grain quality including ratio of grain length to grain width, gelatinization temperature and gel consistency, were significantly influenced by lodging and thus deteriorated. Regression analysis suggested that, lodging one day earlier at the grain-filling stage could cause 2.66% to 2.71% of yield loss, 1.8 to 2.6 percentage points decrease of seed-setting rate, 0.26 to 0.32 g reduction of lO00-grain weight, 0.097 to 0. 155 percentage point decline of milled rice rate, as well as 0.13 to 0.27 percentage point increase of chalky grain rate, and 0.021 to 0.024 percentage point rise of protein content, and subsequently lower the eating quality.

关键词： rice lodging filling stage yield grain quality

Telomere erosion is independent of microsatellite instability but related to loss of heterozygosity in gastric cancer

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World Journal of Gastroenterology 2001年第4期7卷 522-526页

作者： Dian-Chun Fang Shi-Ming yang xiao-dong Zhou dong-Xu Wang Yuan-Hui Luo Department of Gastroenterology,Southwest Hospital,Third Military Medical University,Chongqing 400038,China Southwest Hospital Third Military Medical University Chongqing 400038China. fangdianchun@***

AIM: To correlate the length of the telomere to microsatellite instability (MSI) and loss of heterozygosity (LOH) of APC, MCC and DCC genes in gastric carcinomas. METHODS: Telomeric restriction fragment (TRF) length of gastric cancer was measured with Southern blot. LOH of APC, MCC and DCC genes, microsatellite instability (MSI) and frameshift mutation of hMSH6, TGF-betaRII and BAX genes were analyzed by PCR-based methods. RESULTS: Sixty-eight cases of sporadic gastric carcinoma were studied for MSI using five microsatellite markers. MSI in at least one locus was detected in 17 (25%) of 68 tumors analyzed. Frameshift mutations of hMSH6, TGF-betaRII and BAX were detected in 2,6 and 3 of gastric carcinomas respectively showing high MSI (> or = 2 loci, n = 8), but none was found in those showing low MSI (only one locus, n = 9) or MSS (tumor lacking MSI or stable, n = 51). Thirty-five cases, including all high MSI and low MSI, were studied for TRF. The mean TRF length was not correlated with clinicopathological parameters. No association was observed between TRF length and MSI or frameshift mutation. On the contrary, LOH at the DCC locus was related to telomere shortening (P<0.01). This tendency was also observed in APC and MCC genes, although there was no statistical significance. CONCLUSION: The development of gastric cancer can arise through two different genetic pathways. In high MSI gastric cancers, defective mismatch repair allows mutations to accumulate and generate the high MSI phenotype. In gastric cancers showing either low MSI or MSS, multiple deletions may represent the LOH pathway. Telomere erosion is independent of high MSI phenotype but related to the LOH pathway in gastric cancer.

关键词： Adult Aged DNA, Neoplasm Female Frameshift Mutation Humans Loss of Heterozygosity Male Microsatellite Repeats Middle Aged Research Support, Non-U.S. Gov't Stomach Neoplasms Telomere

基于偏振干涉成像光谱仪的视场增强和相位热漂移补偿关键技术的研究

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光谱学与光谱分析 2016年第11期36卷 3720-3725页

作者：翟洋肖东李博朱日宏中国科学院国家天文台南京天文光学技术研究所江苏南京210042 中国科学院天文光学技术重点实验室江苏南京210042 南京理工大学电子工程与光电技术学院江苏南京210094

偏振干涉成像光谱技术以傅里叶变换光谱学为理论基础,以一系列起偏/检骗器、剪切分束器和延时晶体等双折射晶体材料为主要结构,较之传统光栅式色散型光谱仪具有多通道、图谱合一、大光通量、高信噪比和抗环境振动干扰等一系列优点,并且... 详细信息

偏振干涉成像光谱技术以傅里叶变换光谱学为理论基础,以一系列起偏/检骗器、剪切分束器和延时晶体等双折射晶体材料为主要结构,较之传统光栅式色散型光谱仪具有多通道、图谱合一、大光通量、高信噪比和抗环境振动干扰等一系列优点,并且结合多普勒光谱学相关原理和技术,已被广泛应用在各种天文学和天体物理学测试与计量领域如空间遥感、视向速度、宇航飞行、月球探测等。但是许多前人研究工作中仍然存在两个尚未妥善解决的问题:(1)视场受限。普通型偏振干涉成像光谱仪存在远场条纹的弯曲而使系统视场角限制在±2°以内,严重影响傅里叶变换后的光谱重构精度;(2)相位热漂移。晶体的热胀冷缩和双折射率之差随温度变化的特性导致像面干涉条纹发生随机抖动误差,将严重影响以多普勒频移为原理的视向速度等测量精度。因此,首先引入一块半波片构成增强型的Savart剪切分束器实现主动的视场展宽,可以使增强后的观察视场角达到±10°左右。这一改进不仅提高了傅里叶光谱变换的算法精度,同时也大幅增加光通量从而实现对微光光谱进行高信噪比的探测与标定。另外,为了消除环境温度造成的相位热漂移误差,选用偏硼酸钡(α-BBO)和铌酸锂(LiNbO3)两种晶体进行精密组合匹配。该关键技术利用这两种晶体的双折射率之差随温度变化的相反特性,从而实现相位热漂移误差补偿。实验证明,在实验室环境温度下热相位漂移误差不超过0.02rad。通过这些方案改善偏振干涉成像光谱仪的测试精度,拟实现对天文光梳以及其他大型天文光谱仪器快速而精确的标定与测试。

关键词：干涉成像光谱傅里叶变换光谱学多普勒光谱学天文光梳视场展宽相位热漂移补偿

Improved Efficiency Droop in a GaN-Based Light-Emitting Diode with an AlInN Electron-Blocking Layer

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Chinese Physics Letters 2012年第9期29卷 174-176页

作者： WEN xiao-Xia yang xiao-dong HE Miao LI yang WANG Geng LU Ping-Yuan QIAN Wei-Ning LI Yun ZHANG Wei-Wei WU Wen-Bo CHEN Fang-Sheng DING Li-Zhen Laboratory of Micro-nano Photonic Functional Materials and Devices of Guangdong Province Institute of Optoelectronic Materials and TechnologySouth China Normal UniversityGuangzhou 510631 The School of Chemistry The University of St.AndrewsFife KY169SU.K.

GaN-based light-emitting devices(LEDs)with different electron blocking layers are theoretically studied and compared by using the advanced physical models of a semiconductor device simulation *** is found that the structure with an AlInN electron blocking layer shows improved light output power,lower current leakage and efficiency *** on numerical simulation and analysis,these improvements of the electrical and optical characteristics are mainly accounted for by efficient electron *** can be concluded that Auger recombination is responsible for the dominant origin of the efficiency droop of a GaN-based LED as current increases.

关键词： Efficiency GaN Electron